This example compares the results for multiple systems (known operating times) data.
Reference Case
MIL-HDBK-189A, Section 6.3.1.6.4, pg. 156, 2009.
Data
The following table shows the data.
Prototype #1
Prototype #2
Cumulative Time
*2.6
0
2.6
*16.5
0
16.5
*16.5
0
16.5
*17
0
17
20.5
*0.9
21.4
25.3
*3.8
29.1
28.7
*4.6
33.3
*41.8
14.7
56.5
*45.5
17.6
63.1
48.6
*22
70.6
49.6
*23.4
73
*51.4
26.3
77.7
*58.2
35.7
93.9
59
*36.5
95.5
60.5
*37.6
98.1
*61.9
39.1
101.1
*76.6
55.4
132
81.1
*61.1
142.2
*84.1
63.6
147.7
*84.7
64.3
149
*94.6
72.6
167.2
104.8
*85.9
190.7
105.9
*87.1
193
*108.8
89.9
198.7
132.4
*119.5
251.9
132.4
*150.1
282.5
132.4
*153.7
286.1
Termination Time = 300 hours
(* = system failed)
Result
The book has the following results:
Beta = 0.716, Lambda = 0.454
DMTBF = 15.5 hours
Using significance level = 0.05. CVM = 0.091. Critical value = 0.218. Since CVM < critical value can fail to reject hypothesis that model fits the data.